The present disclosure relates to thin-film transistors (TFTs) and/or other electronic devices comprising a semiconducting bilayer. The semiconducting bilayer comprises a first sublayer and a second sublayer. Devices comprising the semiconducting bilayer of a device exhibit high mobility and excellent.
TFTs are generally composed of, on a substrate, an electrically conductive gate electrode, source and drain electrodes, an electrically insulating gate dielectric layer which separate the gate electrode from the source and drain electrodes, and a semiconducting layer which is in contact with the gate dielectric layer and bridges the source and drain electrodes. Their performance can be determined by the field effect mobility and the current on/off ratio of the overall transistor. High mobility and high on/off ratio are desired.
Organic thin-film transistors (OTFTs) can be used in applications such as radio frequency identification (RFID) tags and backplane switching circuits for displays, such as signage, readers, and liquid crystal displays, where high switching speeds and/or high density are not essential. They also have attractive mechanical properties such as being physically compact, lightweight, and flexible.
Organic thin-film transistors can be fabricated using low-cost solution-based patterning and deposition techniques, such as spin coating, solution casting, dip coating, stencil/screen printing, flexography, gravure, offset printing, ink jet-printing, micro-contact printing, and the like. To enable the use of these solution-based processes in fabricating thin-film transistor circuits, solution processable materials are therefore required. However, organic or polymeric semiconductors formed by solution processing tend to suffer from limited solubility, air sensitivity, and especially low field-effect mobility. This poor performance may be attributable to the poor film-forming nature of small molecules.
It would be desirable to develop semiconducting compounds that exhibit high field effect mobility and good film-forming properties.